When drivers and teams change from racing on asphalt to dirt, the entire approach to drivi
Drivers and teams sometimes find themselves wanting to change venues and switch from their current form of racing to another. The most common change is from asphalt to dirt. Let's take a look at some of the differences and challenges we may face when switching.
We have spoken to a few drivers who have made the switch, and we got their perspectives on the subject. First, we spoke with an old friend, Red Farmer, who at the ripe old age of he-won't-tell-ya, races on a regular basis at the Talladega dirt short track. If you remember, Red was part of the Alabama Gang, which dominated the NASCAR tracks years ago. He now gets his kicks racing his Rayburn and GRT Dirt Late Models at places such as Eldora or the Talladega Short Track.
Red was very vocal about the difficulties a driver encounters when switching from asphalt to dirt. "An asphalt driver is in for a world of hurt if he has no experience on dirt," he said. He thinks it may take a year or two to fully learn how to drive on dirt. "Drivers such as NASCAR's Tony Stewart and Carl Edwards are much better asphalt drivers because of their early dirt experience. I've seen them do things and recover from situations where strictly asphalt drivers lock up the brakes and spin out." he added.
As for the setup end of things, Red said he has personally worked with all of the complexities of the dirt cars over the years with much success, considering his senior status: "At the dirt tracks, we go through four different transitions throughout a day of racing. I am constantly making changes to the car to react to the conditions at any given moment."
Chris Douglas prepares to race his dirt Modified car after running strictly on asphalt for
Chris Douglas is another asphalt racer who has discovered the attraction and thrill of dirt racing. Chris works for Comp Cams' marketing division and has raced on asphalt for over six years. He switched to dirt racing this year and drives a dirt Modified car now. He is making good progress with the transition.
"My biggest problem starting out was getting confident with the car going into the corners," he said. "On asphalt, we always know the grip level, and it is consistent. On dirt, the only way to know for sure is to go beyond the limit and adjust." Then he added something that only true dirt racers know: "You can crutch an ill-handling dirt car much more so than an asphalt car. With asphalt, what you have is all you'll get. On dirt we are constantly trying different entries, different lines to find the quickest lap."
Chris is doing well after only 12 races, and is running in the Top 5 each week. He's doing a little traveling, too, and ran in the Modified division at Batesville, Arkansas, this year during the Topless 100 weekend.
We will also take a look at the construction of the cars as well as the setup quirks of each and how we must change the way we approach chassis setup for the two types of racing.
Track preparation is always important to creating a consistent track surface on dirt. The
The most obvious change is the track's surface. Asphalt is hard, fairly smooth in most cases, and stays consistent in the amount of grip it gives. Dirt, on the other hand, can be in any condition under the sun depending on the material used for the surface, the grading, the moisture content, and whether or not ruts and holes have developed over the course of an event.
So we can safely say that dirt is much harder to plan for because of its ever-changing characteristics. Most dirt tracks start out fairly tight with lots of grip due to the track crew watering it during the afternoon before the first practice. Then, as the event proceeds, the surface material becomes drier and more compact and may either go to a black-slick condition or become very dry-slick with loose material covering the surface.
A team must constantly evaluate the changing grip characteristics and be ready to make adjustments in order to be successful on a dirt track. A team that shows up with one setup and one design of tire will usually be good for just one segment of the event. If the car is set up for higher g-forces, then it will be good in practice and maybe qualifying.
As more laps are run through the heat races, the track becomes more slick and the g-forces go down. The setup that was good at a higher level of g-force is considered loose. If the team does not make appropriate changes, then the car will not be able to get off the corners well and will finish in the back of the pack.
Not only must the team be willing to make setup changes, it also has to know exactly what changes to make and how far to go with those changes. Here are a few general tips on making setup changes from tight to loose conditions.
Even Scott Bloomquist, in the No. 0 car, considered racing on asphalt a while back, and so
1 Start out with a setup that performs under tight conditions. That would involve running a stiffer right-front (RF) spring, a stiffer right-rear (RR) spring, a higher Panhard/J-bar, having the weight lower in the car, more left-side weight, less rear steer, and less bite (referred to as crossweight in asphalt racing). Keep these settings until the track packs down and starts to lose moisture and grip.
The cars that are running laps before you go out will be going sideways on entry and mid-turn and will lose grip on exit under acceleration. Always observe the attitude of the cars that run the track just prior to your going out.
2 As the track starts to lose some grip and smooth out, begin to soften the RR spring, drop the J-bar a little, move weight to the right and up a little, and consider softening the RF spring's rate.
It's not time to get too radical with those changes, and we should develop a series of changes in four stages. This should adequately cover early practice, qualifying, heat races, and the main event.
3 After the heat races have run, the track crew may water the surface again. But since it is packed tight at this point, the water does not penetrate as well and any grip that may come with the water quickly goes away. The surface is usually slick when the feature begins.
Depending on the particular track (this is where experience with each different track comes in handy), it will go to hard and black-slick with moderate grip, or very dry and sandy-slick with very little grip. If you have followed the progression of the grip of the track, then you probably have qualified well and will run well in the heat races and the main event.
Air pressure and stagger are the only adjustments allowed for asphalt tires. That isn't th
There is a vast difference between the design of the chassis for the asphalt car and that of the dirt car in the Late Model touring divisions. There are few chassis adjustments on an asphalt car compared to numerous adjustments on a dirt car. Here is a list of critical adjustments that can be made to each type of car.
Asphalt Chassis Adjustments:1 Springs (4): Usually not changed once the correct rates are found.
2 Shocks (4): Usually not changed once the correct settings are found.
3 Panhard/J-bar: Height and angle not changed throughout an event if the car is well balanced.
4 Weight distribution: Crossweight only in small increments.
5 Antidive and antisquat: Set at the shop.
6 Sway bar preload: Small changes to fine-tune the setup.
Dirt Chassis Adjustments:1 Spring rates: Up to six springs, including the lift arm and pull bar-changed often.
2 Spring placement: Movement to front or rear of the rear axle.
3 Spring attachment: Clamped or not, it's changed often.
4 The four corner shocks: Adjustable for rebound and compression and changed often.
5 Lift bar/pull bar shocks: One or two are changed or reset often for rebound and compression.
6 Panhard/J-bar: Height and angles are critical-adjusted often.
7 Weight distribution: Bite as well as physically moving weight in the car-changed often.
8 Rear trailing arm angle changes occur often.
There are more chassis tuning areas for dirt cars, and each one can and should be changed often to meet the changing conditions of the track surface. If you calculate the number of combinations, the dirt car becomes very complicated and difficult to handle.
The run-to-run adjustments for dirt include weight changes, rear steer changes, spring changes (four corners and lift arm/pull bar), spring mounting position, J-bar height and angle, stagger, tire compound, and tread design. That's a lot for anyone, and novice dirt trackers spend a lot of time confused.
Air pressure and stagger are the only adjustments allowed for asphalt tires. That isn't th
Most of the time, teams running on asphalt tracks use the same mandated tire for the entire event and only adjust air pressure and stagger. It is an entirely different and more complex story for dirt racing. Not only are there several tread and compound designs to choose from, but also the teams alter the tread pattern by cutting out blocks of rubber and siping (making small cuts in the rubber) to change the grip characteristics as well as the cooling properties of the tire.
A dirt tire on a wet tacky surface needs large grooves and no small crevices in order to shed the wet material quickly. Once the track is packed and starts the transition toward slick, more edges are needed to get a grip on the track surface. The siping cuts help cool the tire by releasing the heat generated from sliding across the slick surface.
The art is knowing when to make changes along with knowing what changes are needed at a given point in time. On dirt, the car is not able to utilize the positive properties of a good setup if the tires are not right. It may take several seasons of hard learning to be able to accurately guess the needs of your dirt tires.
Dalton Zehr prepares for practice in the Circle Track Modified car as his dad, Marty, look
There is no need to underestimate asphalt driving by calling it a day at the park. It's somewhat more difficult than it looks on TV or from the grandstands. There is a difference between a good asphalt driver and one who needs more seat time or a different inheritance of chromosome. The asphalt driver seeks a more consistent and smooth driving style while he or she learns how to pass and defend a position. The less the driver has to turn the steering wheel, the better. That isn't true in dirt track racing.
Dirt competitors also strive for smoothness, but they contend with the car at all kinds of attitudes along the way. That entails lots of steering input while your posterior tells you where to steer and how far. Running a few inches off your competitor's door is a little more difficult at speed and at a 45-degree angle to the direction of travel.
A common predicament among several new-to-dirt drivers is knowing where straight-ahead is with the steering wheel. Most entries involve steering first to the left and then right, and then left again coming up off the corner. If the car gets too far around at mid-turn, the driver's hands can get crossed up and he or she loses the sense of where the wheels are straight-ahead.
Chris had to tape the steering wheel at the top at dead straight-ahead to have a point of reference. Dalton, having experienced the same problem, now puts his hands in the 10 and 2 "clock" positions instead of the usual 10 and 4 he was used to on asphalt.
Despite the complexities of dirt track racing, lots of teams and fans love to compete and watch. It's no wonder dirt racing represents over 60 percent of the short track circle track racing that goes on in America. If you haven't tried it, you would be doing yourself a huge favor by accelerating your learning curve.